Saturday, 19 December 2015

Leishmaniasis a 'flesh-eating' disease is currently spreading across Syria

As if years of war, terrorism and oppression weren’t harrowing enough for the people of Syria, the country is experiencing
an epidemic of a so-called flesh-eating disease. Outbreaks of the
disease, known as leishmaniasis, have been reported repeatedly over the past year.
More recently, the head of the Kurdish Red Crescent was reported
to have said the problem was made worse by the actions of Islamic State
leaving bodies to rot in the streets. But while leishmaniasis is a
serious problem in Syria, this picture of a flesh-eating disease spread
by terrorists isn’t entirely accurate.
Leishmaniasis has actually been endemic to Syria for centuries
and was once commonly known as "Aleppo evil". This cutaneous
(skin-affecting) form of the disease isn’t strictly 'flesh eating',
although another form found in Brazil and some other parts of South
America can be. It is caused by the Leishmania parasite, which is carried by sandflies. If you’re bitten by a fly, the parasites
can enter your blood and invade the macrophage immune cells that
normally kill bugs, causing causing horrible open sores close to the
bite.
In other places, in particular India, a different form of the
parasite spreads to the liver and spleen and causes death as those vital
visceral organs break down. In the Brazilian form,
the parasites cause macrophages to migrate to the mucosal surfaces
around the mouth and nose. Here the immune system attacks the parasites
but ends up causing substantial damage to surrounding tissue, eating
away the flesh in these areas, leading to gross disfigurements.
Sandflies actually don’t eat rotting bodies on the street, they
suck blood from living people, so the reports about Islamic State
spreading the disease aren’t strictly true. However, the political
events in Syria - including the rise of Islamic State - have caused the
collapse of the country’s health systems, along with every other part of
the social structure there. So inevitably, the disease has been spreading more widely.

Can it be treated?

Today, around 1.3 million people
are infected with leishmaniasis every year across the tropics and
sub-tropics. Most sufferers have the cutaneous form, as found in Syria,
while the visceral form can be fatal. But because it is typically found
among the world’s poorest people, it receives little attention in terms
of developing new drugs or vaccines and is considered a neglected tropical disease.
However, treatments do exist and in a functioning health system
drugs can be used to cure the disease. Scientists are still debating the
best treatment
for the cutaneous disease but at present we have four different drugs
that can be used. The best medicine for visceral leishmaniasis is called
amphotericin B
and when injected it is very efficient at curing the disease. Just a
few injections of the drug can be enough to cure the disease, but it
does carry the risk of side effects such as fever, headaches and
vomiting.
Older drugs have to be given for several weeks to show an effect. For example, when TV adventurer Ben Fogle
caught the cutaneous disease in Peru a few years ago he was treated
with a rather toxic antimony-based drug, which made him feel very ill
and lose large amounts of weight but eventually cured him.

Could it spread more widely?

In addition to the increasing incidence of the disease in Syria
itself, some refugees fleeing the country will carry parasites with
them. This could be used by those who oppose taking in refugees by
suggesting they will spread disease. But countries receiving refugees
need not worry about its introduction.
It is sandflies, not people, that transmit the disease and though
they are found throughout the tropics and subtropics, they can’t
survive in colder climates. The visceral form of leishmaniasis is
already endemic in parts of southern Europe
including Spain, Italy and the south of France, but the disease tends
to only manifest itself in people with weak immune systems such as those
infected with HIV. This highlights the fact that people in prosperous
regions where nutrition and general health are good are at limited risk.
It is also important to understand that different species of sandfly are responsible for transmission of different Leishmania
parasites. Those that transmit the cutaneous disease found in Syria are
less common in southern Europe so the chances of increasing
transmission of cutaneous leishmaniasis are small. Although Turkey might
be at risk of increased incidence of the cutaneous disease due to the
flow of refugees from Syria, again it is worth highlighting that people
with access to good nutrition and in generally good health are less
vulnerable.
Concerns about imported germs, of course, are nothing new. Just last year, European airports were decorated with posters warning of Ebola,
and those coming from West Africa were subjected to mandatory tests for
signs of fever. But we should be careful of warnings of diseases
spreading to developed countries, where healthcare systems and levels of
public health are much more capable of preventing and treating
infectious condition, even in instances where those diseases could
spread. Plus the wider availability of treatments in Europe creates an
opportunity to provide healthcare to incoming sick refugees.
Given that leishmaniasis cannot be spread to colder countries and
is limited by good healthcare, the particular suggestion that it could
be carried by refugees holds no force.